Uninterruptible power supply



FIG. 1 is a perspective view of an uninterruptible power supply showing our new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a right side elevational view thereof;

FIG. 5 is a left side elevational view thereof;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof.

The broken lines shown represent unclaimed subject matter and form no part of the claimed design. 

The ornamental design for an uninterruptible power supply, as shown and described. 